icz (voiceover): his sentence-- 15 years to life. josh mankiewicz: you told me that you thought you had let this consume your life too much. oh, it did. it does to this day. well, now it's over. what are you going to do? i don't know. a new life is opening up to you, and i don't-- i don't know. i don't have any answers. i just have to get over this. and that's all for this edition of "dateline." i'm craig melvin. thank you for watching. [theme music] hello, i'm craig melvin, and this is "dateline." hello, i'm craig melvin, a i fell to the floor." i just remember, like, she's dead, she's dead.

and i was so confused. i was like, what's going on? what happened? craig melvin (voiceover): a small texas town. two super close friends and a summer night in the park. they have this look out. and you could see the harbor bridge lit up, it's really pretty when the stars are out. craig melvin (voiceover): it was the next morning that they found them. i could see two girls laying there. it was horrifying. there was duct tape on their mouths, on their hands. craig melvin (voiceover): a mystifying scene. the only thing we have are cigarette butts and suspicion. craig melvin (voiceover): dna would point one way. he's like, sarge, you got to take a look at this. craig melvin (voiceover): a bombshell message would point another. i read the letter and immediately knew this was something very important. craig melvin (voiceover): a twisted trail leading to a sinister suspect. it takes a special kind of mind that wants to do something like that. craig melvin (voiceover): to crack a case this convoluted, it might just take a miracle.

that was extraordinary. i just couldn't believe it. welcome to "dateline." two young women were discovered in a park bound and gagged. both were sexually assaulted and shot in the head. one died, but the other miraculously was still alive. some wondered-- could a secret relationship have been the motive for murder? here's josh mankiewicz with "a texas twist." josh mankiewicz (voiceover): named for the body of christ, corpus christi sits on the texas gulf coast. and just east of the bay is a park known for birdwatching, and that's what chris seymour was doing there when he came across something very unnatural. to me it just looked like a pile of debris, to be honest.

and then he looked and, he said oh, my god. it's two bodies. josh mankiewicz (voiceover): a crime so shocking that years later, they're still talking about it. i can't even imagine what was in that person's mind that evoked his violence, his rage. josh mankiewicz (voiceover): two young women. who wanted them dead? and why? it was a true who-done-it type murder. josh mankiewicz (voiceover): and along with who and why was the question of why here. this was definitely something that we weren't used to or accustomed to in our town. josh mankiewicz (voiceover): this part of texas isn't exactly ground zero for murder. it's known more for roping, riding, and friday night lights. here, life is pretty simple as are the values its people hold dear like friendship,

family, community. this is where 19-year-old mollie olgin grew up. tell me a little bit about what she was like. she was really funny. she had a weird sense of humor. always smiling, laughing. she's just a really good person. megan olgin was mollie's older sister, just two years apart. they were, says megan, fiercely competitive. she was really smart, which i was always kind of jealous because math came so easy to her. all the subjects came easier. she didn't even have to study, try, nothing. josh mankiewicz (voiceover): mollie also played drums in the high school band but her friends brooke ostrom and stephanie chasak say that what mollie really loved was cruising down the highway, singing along to bands like the spice girls. that's mollie behind the wheel. she loved her car, a lot. i remember one night she decided i'm going to name my car jabbar.

after that she called her car jabbar my car. and it was the funniest thing for no reason. josh mankiewicz (voiceover): smart, funny, and a car owner. all of which made for one very popular teen. josh mankiewicz: she had a lot of friends. - yes. - oh, yeah. - a lot of friends. - yeah. she never let anybody leave from hanging out with her without giving them a hug. and saying i love you. ever. josh mankiewicz (voiceover): which was certainly true when it came to the newest member of mali's unusually large posse of friends-- 18-year-old kristene chapa. could you tell they really liked each other? - yeah. - yeah. mollie talked about her a lot. josh mankiewicz (voiceover): kristene lived in a neighboring town where she was earning a reputation as a softball superstar. kristene was a softball icon for this town. josh mankiewicz (voiceover): brittany selby was kristene's close friend. she was like the comic relief in our little group of friends. josh mankiewicz (voiceover): brittany says kristene's sense of humor was a perfect match for mollie's.

mollie definitely brought out kristene's crazy side. it was never, never a dull moment with those two. josh mankiewicz (voiceover): but for this group of girls, crazy and dull were relative terms. we were not the party kids. we never drank or anything like that. we would go to taco bell, we would go to coffee shops, and we would go to parks. josh mankiewicz (voiceover): which is exactly what mollie and kristene decided to do on a warm summer night back in june of 2012. their destination-- violet andrews park. that place seem safe to you? yeah. yeah, it did. all of the parks were, i mean, we would go-- we would go at night all the time. josh mankiewicz (voiceover): before heading out, the two called brittany, asking if she wanted to join them. brittany took a pass. they had asked me to go, but i had a volleyball game the next morning so i wasn't able to. josh mankiewicz (voiceover): it was a decision that still haunts her. i just know, because they, like, you know,

they called me that night. i'm like, if i was there-- josh mankiewicz (voiceover): the next morning, chris and stan seymour were strolling through violet andrews park. we started looking around for birds in general. didn't see a thing. this place was as quiet as we'd ever seen it. josh mankiewicz (voiceover): and that's when, just below one of the overlooks, they made their terrible discovery. in the tall beech grass lay the bodies of two young women. it just looked like they had both been molested or mauled. we didn't know if they were alive or dead. we had no idea. josh mankiewicz (voiceover): the seymour's ran for help. first responder travis wiesman had never seen anything like it. it was horrifying. there is blood. i can see that the clothes are off both girls. there was duct tape on their mouths, on their hands.

you could see they were clearly bound. josh mankiewicz (voiceover): duct tape also covered their eyes. and each girl had been shot in the back of the head. i went and checked the pulse on the first girl. i could feel her body was cold and didn't feel a pulse. josh mankiewicz (voiceover): and then something no one expected. i went to reach for the second girl and that's when she started to sit up and moan. it looked so hopeless. and to think that one was alive was just a miracle. josh mankiewicz (voiceover): which girl had survived? could doctors keep her alive? and what story could she tell? the questions were just beginning. one victim surviving. the first surprise in a case teeming with twists. investigators focus on one particular clue. craig melvin (voiceover): coming up. sometimes that can suggest somebody who knows the victim. yes. craig melvin (voiceover): when "dateline" continues.

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the most accurate cgm. josh mankiewicz (voiceover): as dawn gave way to morning on that june day in 2012, news of a double shooting in one of the parks began to slowly spread throughout the texas gulf coast. stephanie chasak and brooke ostrom learned about it on facebook. didn't say who it was. didn't say male or female or anything along those lines.

you didn't think it would be anybody you knew. i didn't think it'd be anybody i knew. josh mankiewicz (voiceover): brittany selby tried to call both kristene and mollie. neither one of them is picking up, so that's when i started to get worried. josh mankiewicz (voiceover): kristene's parents, grace and larry chapa, were worried, too. grace had been pacing the floor ever since she discovered kristene hadn't come home the night before. josh mankiewicz: that's unusual. and that was very unusual. by now, how many times have you called your daughter? i would say about four or five times i called her. i even told her, i'm going to call the police if you don't call me right now. josh mankiewicz (voiceover): which is just what grace did. that's when she learned kristene had been hurt. but the officer wouldn't say much else, only that grace needed to get to memorial hospital. he doesn't tell you what happened? no, he doesn't know what happened. josh mankiewicz (voiceover): it was only after arriving at the hospital that the chapas. learned kristene had been shot but they still didn't know if kristene was alive or dead.

the nurse walks in and tells us one girl died, and one girl is on the second floor and we need to identify her. and they don't know who died and who lived? no. josh mankiewicz (voiceover): it was up to the chapas to identify the survivor. you couldn't go? i couldn't go. i couldn't do it. josh mankiewicz (voiceover): so grace assigned her eldest daughter that grim task. so the best you're going to hope for here is that it's your daughter but she's-- she's hurt. josh mankiewicz: already pretty seriously hurt. mm-hmm. josh mankiewicz (voiceover): for the chapas, the wait was excruciating. and then their daughter returned with the news they had been praying for. she comes back down and she tells me, mom, it's kris. josh mankiewicz (voiceover): family and friends took turns at kristene's bedside wondering if she would ever regain consciousness. i was talking to her, telling her that i was there, you know. and that we loved her, you know. josh mankiewicz: how'd she look? it was bad. it was so bad that you couldn't even--

you didn't know it was her. josh mankiewicz (voiceover): the bullet had entered the right side of kristene chapa's head and shattered, destroying some of her brain tissue. during a lengthy surgery, doctors decided not to try to retrieve the bullet fragments. but at least kristene was still alive. by now, the other victim had been identified as mollie olgin. and news of mollie's death had reached her family. i was in shock. i remember crying really hard. and i was throwing stuff in my room because it just didn't seem real to me. how are your parents? really emotional. i'd never seen my dad cry. they took it really hard. josh mankiewicz (voiceover): so did mollie's friends, stephanie and brooke. i just remember, like, she's dead, she's dead. and everyone was like, who's dead? and i said, mollie.

josh mankiewicz (voiceover): over the next few days, neighbors here began asking the same question. who had pulled the trigger and why? finding those answers fell to portland texas police detective roland chavez. mollie can't give us any information. and kristene's in the hospital, and she can't give us any information. at that point not even clear whether kristene's-- going to survive. josh mankiewicz: right. josh mankiewicz (voiceover): tips were coming in. someone said they saw a white car speeding from the park the night of the shootings. that led nowhere, so chavez and his team focused on the crime scene. there was no murder weapon. they did find two spent .45-caliber casings. and near an observation deck, just 30 feet away from where mollie and kristene were discovered, police found an empty monster energy drink can and five cigarette butts. josh mankiewicz: and the girls didn't smoke. the girls did not smoke. josh mankiewicz (voiceover): chavez sent all that for dna testing. as for the duct tape used to cover the girl's eyes,

chavez thought maybe that was itself a clue. sometimes that can suggest somebody who knows the victim, didn't want to see them. mm-hmm as far as you know, either of them have any enemies? no, that's what was so confusing. everyone loved them, you know? josh mankiewicz (voiceover): and that's probably why they were all so discreet when it came to kristene and mollie. now, as a murder investigation began, friends revealed something that not many knew. they began to tell us they were in a relationship. these weren't just two friends. they were dating. - yes. josh mankiewicz (voiceover): that had many here wondering if a romance that was hidden from many might have in some way been a motive for the attack. conceivable that this was some kind of hate crime? i mean, i'd be lying if i said that thought didn't cross through my mind. josh mankiewicz (voiceover): three days later came news from the hospital-- kristene chapa had regained consciousness. we're hoping now we're going to be able to really

get the ball rolling. josh mankiewicz (voiceover): the story kristene eventually shared with police provided intriguing clues about the identity of her attacker. and it's a story kristene will also share with you. craig melvin (voiceover): coming up. kristene's harrowing account. the first thing we asked her, of course, is did you know the person that did this? craig melvin (voiceover): when "dateline" continues. [coughing] copd isn't pretty. i'm out of breath, and often out of the picture. but this is my story. ( ♪♪ ) and with once-daily trelegy, it can still be beautiful. because with 3 medicines in 1 inhaler, trelegy keeps my airways open for a full 24 hours and prevents future flare-ups. trelegy also improves lung function, so i can breathe more freely all day and night.

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josh mankiewicz (voiceover): larry and grace chapa kept a sleepless vigil over their daughter kristene as she lay in the icu, hovering somewhere between life and death. the 18-year-old had been shot in the head and left outside for more than eight hours. somehow she'd survived. then, just days after her brain surgery, kristene again defied the odds and began to stir. that's an incredible little girl here, i'm telling you. she is something else. we asked her questions, she would squeeze our hand. that must have been a wonderful thing to see. it was. josh mankiewicz (voiceover): for police, the pressure to find the shooter was intense. detective roland chavez hoped kristene, now conscious, would be playing a big part in that. but kristene still could not speak. it was either a squeeze of the hand and then the blinking of the eyes.

josh mankiewicz (voiceover): so chavez kept his questions simple. the first thing we asked her, of course, is did you know the person that did this? and she said no. and how tall was he? she described him as about 5' 8", 5' 9". josh mankiewicz (voiceover): within the first two weeks of her recovery, kristene helped police draw this sketch of the man who shot her. she said he smelled of cigarettes, which made chavez think about those cigarette butts found at the crime scene. he asked that the dna tests on those be put on the fast track. one of the things that kristene was also able to give us was that the assailant wore gloves, and under armor gloves specifically. she on the logo. yes. and she was a softball player, so she's saying under armor gloves then under armor gloves is probably exactly what we're looking for. josh mankiewicz (voiceover): but during those sessions with kristene, chavez wasn't the only one asking questions. kristene struggled to ask a few of her own.

tough ones. josh mankiewicz: was kristene asking you about mollie? she did. we did not initially give her any of that information. josh mankiewicz (voiceover): both chavez and kristene's parents were afraid that the truth about mollie would upset kristene and maybe jeopardize her recovery. i would just tell her, mollie's got got sent to another hospital. josh mankiewicz (voiceover): of course, kristene persisted. and eventually everyone decided she deserved to know mollie's fate. family and doctors assembled in kristene's room when detective chavez revealed the truth. she was distraught and crying. and told her, you know, i just i need you to stay strong so that you can help us. and we're going to catch him. and so she did. josh mankiewicz (voiceover): as the days passed, kristene's communication skills steadily improved, enabling her to share with police more details of that horrible night.

i mean, it's supposed to be peaceful and safe. josh mankiewicz (voiceover): we wanted to hear her story, too. josh mankiewicz: you look great and it's great to see you. thank you. josh mankiewicz (voiceover): kristene began by describing her relationship with mollie. i met mollie at the mall. was there some chemistry right from the beginning? oh, there was. we were both like very sarcastic. and we would just amuse each other and make each other laugh a lot. josh mankiewicz (voiceover): six months later, the two had become a serious couple. then came that june night in the park. why did you go to the park that night? well, because we had missed our movie and so we're kind of driving around and just trying to figure out what to do. josh mankiewicz (voiceover): when they got there, kristene said, she and mollie walked to one of the overlooks. and we weren't even there for five minutes and we end up seeing like this guy walk by. i got this weird feeling, and we wanted to hurry up and get out of there. and the next thing you know, he's right there on mollie's side with a gun. josh mankiewicz (voiceover): she said the man then forced the two girls down a steep embankment

and into the tall beech grass below. and she recalled the odd way he referred to them both. he called mollie and girl number one and i was girl number two. and he referred to you that way? by numbers, all the way through it? he did. what did you say to him? i asked him if he was going to take us anywhere. and he just told me, like, no, this will be quick and easy. i can feel, like, my heart beating so fast. i'm like, man, i want my mom. and that's when i'm just like praying, please, god, don't let-- don't let me die, please. mollie say anything? we both asked each other if we were ok. and that was the last thing we asked, we both asked each other. josh mankiewicz (voiceover): that's when kristene says she was raped. but the ordeal wasn't over. he had the gun pointed at us still and he made me put duct tape over mollie's mouth and her eyes. and i had to do the same to myself.

i was already at that stage, like, i'm going to die, like this is it. and i hear the gun go off. and then i went black, and like everything went black. josh mankiewicz (voiceover): kristene's remarkable physical recovery turned out to be the easier part. i come out here for the anniversary of the shooting, for mollie's birthday, and like for the day we met. this is not a painful place to return to? it's not painful. i guess i just kind of feel closer to her, i guess, because it's the last place i saw her at. josh mankiewicz (voiceover): rehab helped distract kristene from her sadness. so did working with police to find mollie's killer. kristene was kind of our inspiration. seeing how hard she was working just made us continue to work even that much harder for her. josh mankiewicz (voiceover): it wasn't for lack of hard work, but police had to face the truth. the investigation had stalled.

at this point, sounds like you're kind of nowhere. yeah. josh mankiewicz (voiceover): and then the dna tests of the cigarette butts and the drink can came back from the lab. and that changes everything. yes. craig melvin (voiceover): coming up-- a mysterious message rocks the case. the letter is written from the perspective of a hit man who has been hired-- kill the surviving victim in this case, kristene chapa. craig melvin (voiceover): when "dateline" continues. [music playing] tiffany: my daughter is mila. she is 19 months old. she is a little ray of sunshine. one of the happiest babies you'll probably ever meet. [giggles] children with down syndrome typically have a higher risk for developing acute myeloid leukemia, or just leukemia in general. and here we are. marlo thomas: st. jude children's research hospital works day after day to find cures and save

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hi, i'm richard lui with a news update. tropical storm debbie strengthening into a category one hurricane just a few hours ago ahead of its expected landfall in florida today. it will bring strong winds and flooding to the region where the president has already approved an emergency declaration. the u.s. has taken the commanding lead at the paris olympics. team usa earning 28 medals to

bring the total to 71 with historic gold medal win in track and swimming. . kristene chapa told a harrowing tale of being raped at gunpoint by a man she had never met. she remembered her assailant was wearing under armor gloves. was this a detail that could help investigators unlock the mystery? here again is josh mankiewicz with "a texas twist." josh mankiewicz (voiceover): day by day, inch by inch, kristene chapa walked a steady, if uneven, road to recovery. i couldn't move my left side. i couldn't move my hand, or my arm, my leg. i had to relearn to swallow. you don't give up, do you? i don't. i try to stay motivated. josh mankiewicz (voiceover): so did detective roland chavez. he, too was making progress. the cigarette butts in drink can collected from the crime scene had just given him his first major break in the case.

what did the dna show? the dna showed that it returned to dylan spellman. josh mankiewicz (voiceover): who was dylan spellman? police learned he lived just three blocks from the crime scene. and chavez also noticed a striking resemblance to that sketch kristene had helped police draw of the gunman. we start trying to get background on dylan spellman. josh mankiewicz (voiceover): some quick computer searches revealed spellman had a criminal past. dylan spellman had just been convicted of a violent crime. yes. of an armed robbery in nevada. yeah. josh mankiewicz (voiceover): that nevada armed robbery occurred in 2010, a year and a half before the shootings. spellman and some accomplices broke into a home in a las vegas suburb and held a family hostage before robbing them and taking off. josh mankiewicz: anybody get killed? no. josh mankiewicz (voiceover): and at the time of the shootings in 2012, dylan spellman was in the corpus

christi area awaiting sentencing for the nevada armed robbery. he'd been sent here to stay with a friend. josh mankiewicz (voiceover): what intrigued chavez were some unusual similarities between the nevada crime and the shootings in texas. as we started going through that case file, we started seeing more and more things that are lining up with what we're looking at. for example? the use of numbers. josh mankiewicz (voiceover): remember, kristene had said the shooter referred to her and marley as girl one and girl two. he used numbers in that other crime? yes. they referred to each other by number in that particular crime. josh mankiewicz (voiceover): the similarities between the two crimes didn't end there. in the nevada home invasion, were the victims bound? yes, they were. he's got to be number one on the list at this point. he definitely jumped to the top. josh mankiewicz (voiceover): by that time, dylan spellman had already returned to nevada to begin serving his three-year sentence. so chavez hopped a plane to las vegas,

hoping to hear what mr spellman might reveal about his brief stay in texas. spellman admitted he was in the park the night of the shootings, but he denied being anywhere near the area where the girls were found. he said he was never on the deck. well, we've got dna on the cigarette butts that prove otherwise. why lie about that unless you're involved in the crime? sure. so i mean that definitely raised more suspicion. josh mankiewicz (voiceover): chavez then told spellman police found his dna just 30 feet from where the girls were shot. that's when he says spellman demeanor changed. he asked me, you know, what are the consequences? and i said, well, in texas, i said, you know, this is a death penalty kind of case. josh mankiewicz (voiceover): and then dylan spellman asked about a deal. normally, any person that's innocent isn't going to ask for a deal. you're going to profess your innocence and he wasn't. now i'm thinking this is my guy. josh mankiewicz (voiceover): so chavez

asked spellman to take a polygraph and spellman agreed. josh mankiewicz: and how does he do? he fails. josh mankiewicz (voiceover): time for handcuffs, you're thinking? not quite yet. chavez could put dylan spellman at the crime scene, but still had no way of tying him directly to the shootings. we have no gun. we have no usable prints. the only thing we have are cigarette butts, monster can, and suspicion. josh mankiewicz (voiceover): it didn't help that chavez is one eyewitness to the shootings could not identify spellman from a photo lineup. it was very hard because the suspects all looked the same. josh mankiewicz (voiceover): and then there was the matter of mr. spellman's height. he was big. he's what? 6' 8"? 6' 8". josh mankiewicz (voiceover): remember, kristene said the shooter was quite a bit shorter than that. 5' 8", maybe 5' 9". for me, it was always the difficulty of getting over the size.

josh mankiewicz (voiceover): so chavez and his team regrouped. we began getting cell phone records for him, getting hair samples, or anything off the duct tape. anything off of the girl's clothing. anything that would be able to attach dylan spellman to them. does any of that lead anywhere? no. unfortunately, it didn't. josh mankiewicz (voiceover): two years passed. the case grew so cold that chavez's chief decided to give it to a new detective, hoping he might have better luck finding the missing pieces. detective aaron veuleman had been working the case, and now he took the lead. what we first wanted to do was expand the scope of the crime scene search, because there was one crucial piece of evidence that we didn't have at that point which was a murder weapon. josh mankiewicz (voiceover): veuleman hoped the murder weapon might definitively link spellman to the shootings. josh mankiewicz: what did that turn up? we didn't find anything. nothing of value. so you're back to kind of nowhere. that's right. and then? we received a phone call from the investigators at the sinton police department.

josh mankiewicz (voiceover): those investigators in the neighboring town of sinton had just been given a letter addressed to kristene chapa's father. what does the letter say? the letter is written from the perspective of a hit man who has been hired to kill the surviving victim in this case, kristene chapa. josh mankiewicz (voiceover): in the letter, the hit man even named the person who had hired him. if you're wondering, the letter does not mention dylan spellman. all of it was a twist as big as texas. craig melvin (voiceover): coming up. the mysterious letter, could this be the smoking gun police had been looking for? immediately i knew this was something very big and very important. craig melvin (voiceover): when "dateline" continues. most people call leaffilter when their gutters are clogged and they notice one of the many issues that can bring. sometimes it's the smell of mildew

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josh mankiewicz (voiceover): while detective aaron veuleman continued trying to strengthen his case against dylan spellman, investigators in neighboring sinton, texas received a mysterious letter addressed to kristene chapa's dad. immediately i knew this was something very, very big and very important. josh mankiewicz (voiceover): the letter writer described himself as a hit man, hired by the person who shot mollie and kristene. he wrote, the gunman had sought his services to finish the job and make the only witness to mollie's murder disappear.

what he's saying is i was hired to kill kristene, but i'm not going to do it. instead, i'm warning you. that's right he's. telling kristene chapa's father, i'm going to tell you who the murderer is. and then you can go do something about it. josh mankiewicz (voiceover): the letter contained details police had never mentioned in public. that he forced the girls to duct tape themselves. the fact that he called them by numbers, girl number one and girl number two. josh mankiewicz (voiceover): then the biggest revelation of all. who does he say the murderer is? he identifies him. his name is christobal melchor and he gives an address in utah. josh mankiewicz (voiceover): christobal melchor from layton, utah, to be precise, just outside salt lake city. melchor worked in the area as an army reservist. had the name christobal melchor crossed your desk in any way during this investigation? in the two years prior to this investigation, we had never heard that name. josh mankiewicz (voiceover): the hit man

even included a photograph of mr. melchor, the man he said hired him. this guy is being handed to you on a plate. yeah. josh mankiewicz (voiceover): could it be real? should police take this at face value? is it possible this letter is some sort of thinly veiled threat to kristene? you know, you've survived, but we know where you live. yes. the letter definitely contained an implied threat to her safety. and so we moved very quickly to make sure that she was safe, that she was protected. and they're like, ok, you know what? you need to leave town. like, no one can know where i was at. only my family knew where i was at. josh mankiewicz (voiceover): with kristine in a safe place, veuleman went straight to layton, utah. with the help of the local pd, he was soon sitting across from his new person of interest. christobal melchor said that he was on a training exercise in fort hunter liggett, california at the time of the murder. not only was he not in texas, he was on the other side of the country.

he was. was there anything to suggest that he had some kind of vendetta against the chapa family? we were not able to find any connection between christobal melchor and the chapa family or the olgin family. josh mankiewicz (voiceover): veuleman then showed melchor the letter and melchor was stunned. but he was even more surprised when he saw his picture on the last page of the letter. josh mankiewicz (voiceover): that was because melchor immediately recognized the photo. he knew when and where it was taken. plus, he said, the original photograph was of two people. the missing man, he said, was his former roommate, david strickland. if the snapshot was a surprise to melchor, the name david strickland was an even bigger one for detective veuleman. turns out, he'd crossed paths with david strickland before. i'd interviewed david strickland in 2012, just days after the murder. josh mankiewicz (voiceover): remember that tip about a white car seen speeding from the park the night

of the murder? the tipster was david strickland. he came in as a good samaritan wanting to provide information. josh mankiewicz (voiceover): back then, david strickland lived just blocks from the park where the shootings took place. and now here he is being mentioned in connection with a guy who's been mysteriously fingered for the murder. that's right. so just like that, basically, mr. melchor is no longer the focus of this. it's now david strickland. that's right. josh mankiewicz (voiceover): chris melchor went on to explain that he and strickland were no longer on good terms. melchor believed strickland had stolen several of his guns so he had strickland arrested. yeah, the gun robbery put a damper on their relationship. josh mankiewicz (voiceover): strickland pleaded not guilty to the gun theft charge and was released soon after. but the charges were still pending. and veuleman wondered-- could strickland have written that letter as some kind of elaborate payback for melchor having strickland arrested?

i know there was bad blood between david strickland and christobal melchor. but to accuse someone of murder? if you think that letter was written by david strickland, and you think the letter includes things that only the killer would know-- well, i think the logical inference was that strickland had something to do with the murder. josh mankiewicz (voiceover): finding david strickland was now veuleman's priority according. to melchor, strickland left utah after his arrest and returned to texas. so detective veuleman did the same, hoping this man would turn out to be the investigation's third and final person of interest. craig melvin (voiceover): coming up. a suspect, not acting at all like you might expect. so it's like a game? very much so a game. he was enjoying this interview. craig melvin (voiceover): maybe police have the wrong guy again. she doesn't know who shot her. she has no recollection. she wasn't able to pick our client out of a photo lineup. she wasn't able to point at him in court

and say that's the guy that did it. craig melvin (voiceover): when "dateline" continues.

welcome back. a mysterious letter had identified christobal melchor as the man who shot kristene chapa and her girlfriend mollie olgin. after police spoke with melchor, they turned their attention to his former roommate, david strickland.

police wanted to hear what he had to say and they were not the only ones. here's josh mankiewicz with the conclusion of "a texas twist." josh mankiewicz (voiceover): first came dylan spellman, cleared by police and by his height. then chris melchor, also cleared of suspicion by geography. now detective veuleman was on the trail of another man, david strickland. the detective learned strickland was a hometown boy. his dad a successful businessman. strickland served briefly in the military and was now newly married. then veuleman saw photographs of david strickland's possessions, which had been seized at the time of his arrest on the gun theft charge. i'll never forget the first photograph that popped up. it was a glock .45 caliber pistol and an under armor glove. and you could see very clearly the white under armor logo.

josh mankiewicz (voiceover): a glock .45, the type of gun the crime lab suspected was used to shoot the girls. as for the black glove, kristene was absolutely certain that the shooter wore a pair exactly like that. i know that because i played softball and that stuck out to me right away. josh mankiewicz (voiceover): detective veuleman immediately sent strickland's gun to be tested to see if it fired those two spent shell casings found at the crime scene. he didn't have to wait long for the results. what that report said was that the two shell casings found at the scene and the two shell casings from the test fire were linked to the same weapon. josh mankiewicz (voiceover): for detective veuleman, that report was the missing piece of the puzzle, which he believed now directly linked david strickland to the shootings. the day i looked at that ballistics report as the day we arrested david strickland. josh mankiewicz (voiceover): the charges--

aggravated assault, aggravated sexual assault, and capital murder. while in custody, david strickland agreed to sit down for a police interview. san patricio county prosecutor sam smith watched the interview through a one-way mirror. he would claim to have committed the murder. and then in the next sentence, with a smile on his face, saying, but that's what you wanted me to say, isn't it? so it's like a game? very much so a game. he was enjoying this interview. josh mankiewicz (voiceover): four years after kristene chapa was raped and shot, four years after mollie olgin was murdered right next to her, david strickland faced a jury of 12. were you confident? were you worried? well, of course, i was worried.

i mean, i just felt horrible. i didn't know how it was going to end up coming out. when you saw mr. strickland for the first time, what did you think? i didn't know what to think, to be honest. i was just thinking, he did this? he wasn't the monster you imagined. no. he wasn't. sometimes those are the scariest people, though. josh mankiewicz (voiceover): prosecutor smith laid out his evidence from gunshot, to snapshot, to mug shot. the gun, the shell casings, and the gloves. as for the letter, smith told the jury police had found remnants of it on david strickland's computer. you can delete the letter off of your computer. but if you've used the spell-check grammar-check function, that information is still stored in the computer. and that's what you found? and that's what we found. josh mankiewicz (voiceover): before prosecutor smith rested, he called kristene to the stand, putting her face

to face with david strickland. i was trying to make eye contact with him. i wanted him to see me and see what he had done, but he would not look at me. josh mankiewicz (voiceover): defense attorneys john gilmore and jimmy granberry don't dispute that kristene was a sympathetic witness. but in court, they argued, she was also unreliable. she wasn't able to pick our client out of a photo lineup. she wasn't able to point at him in court and say, that's the guy that did it. josh mankiewicz (voiceover): what's more, kristene initially told police the shooter's gun was silver. david's gun is a glock, which is black. josh mankiewicz (voiceover): the defense also went after the investigators, arguing they'd bungle the lengthy two year long investigation by losing critical documents and mishandling evidence. we had the documentation that the evidence was mishandled from the chief of police, chastising the officer who handled the evidence. josh mankiewicz (voiceover): that lead detective, roland chavez, admits mistakes were made. he's now retired.

the second lead detective, aaron veuleman, was let go for sharing sensitive details of the case with someone outside the department. strickland's attorneys concede their client may have written that letter. but they argue it would only have been out of revenge for chris melchor having him arrested. as for those confidential details in the letter-- this is small town texas. there's any number of places that this kind of information could have come from. josh mankiewicz (voiceover): but what about the lab report showing strickland's gun matching the shell casings found at the scene? we had our expert who said that it's inconclusive. i mean, there's no way that you could say for sure. josh mankiewicz (voiceover): police, they said, should never have taken their sites off the real shooter. well, they had the right guy. dylan spellman, you think that's the killer? he's a better match than my boy. he had just failed a polygraph exam and then started trying to plea bargain. this is a guy that kicked in a door with a group of people

wearing masks. went in and held a family hostage, terrorized a family. josh mankiewicz (voiceover): and strickland's attorneys point out their client had no history of violence at all. david strickland did not do this. josh mankiewicz (voiceover): it was sam smith who had the last word. dylan spellman, he told the jury, might have been under suspicion, but ultimately had nothing to do with this crime. david strickland, he said, was the man holding the gun. shooting both of these girls for no identifiable reason at all. he's certainly a psychopath. josh mankiewicz (voiceover): prosecutor smith never offered the jury a possible motive. kristene says she's sure it was about her sexual orientation. what's the reason for thinking it's a hate crime? in the letter that he supposedly try to send to my dad, it said something in the letter like those [muted] lesbians. josh mankiewicz (voiceover): in his interrogation strickland made a point of saying he

had no issues with the gay community. whether or not that was the truth, prosecutors decided not to charge him with a hate crime. after five days of testimony, the jury began deliberations. it took six hours to reach a verdict. guilty. strickland was sentenced to life in prison. backed by a new legal team, strickland appealed, but a court upheld the jury's decision. he plans to keep fighting the conviction. for mollie's family and friends, that guilty verdict, as it often does, provided hollow satisfaction. we were waiting for justice. and then now it's here, but we don't get her back. we have had so many huge, major life moments, and she hasn't been there. what would have been our anniversary and her birthday, the anniversary of us getting shot,

those days are the hardest. josh mankiewicz (voiceover): kristene still wonders how she escaped death and sometimes why. i do have survivor's guilt. i mean, hopefully, it'll go away in time. kristene will tell me, why was it me? why didn't she survive? and i told her, there's a reason she was still living and to be happy, and live on for mollie, because mollie didn't get that chance. that's all for this edition of "dateline." i'm craig melvin. thank you for watching. . okay. kamala harris could announce a running mate at any moment, and debate he already